1. Field of the Invention
This invention relates to a single circumferential chain incorporating a link chain section having opposite ends semi-permanently joined together by a three to four inch expansion spring of the closed coil type extending between the chain section ends with the chain to be stretched over the circumference of a vehicle tire equipped with a central tread area groove for snug seating of the link chain section and the spring within the groove and with the spring in a slightly open coil state.
2. Description of Related Art
Various different forms of central tread groove applied chains and cables heretofore have been provided including those disclosed in U.S. Pat. Nos. 922,631, 985,884, 1,293,528 and 2,276,640. In addition, other similar types of tire tread area traction improving devices have been provided such as those disclosed in U.S. Pat. Nos. 1,489,318 and 3,400,744. However, these previously known devices have not been constructed to allow relatively easy installation thereof on a pneumatic tire when the chain, cable or other traction devices are in a continuous loop form.